The primary datastore used by the server is the Oracle Berkeley DB Java Edition (JE). The server provides two primary sources of information about processing within the database.The first is logging performed by the JE code itself, and is written into the file in the server containing the database files (for example, db/userRoot/ In the event of a problem within JE itself, useful information about the nature of the problem may be written to this log. The level of information written to this log file is controlled by the db-logging-level property in the backend configuration object. It uses the standard Java logging framework for logging messages, so the standard SEVERE, WARNING, INFO, CONFIG, FINE, FINER, and FINEST levels are available.

The second is configuration information used when opening the database environment. When the backend database environment is opened, then the server will also write a file named je.config in the server containing the database files (for example, db/userRoot/je.config) with information about the configuration used.